Textured mantle, keel and striped skirt fringe of big black slug

slug black slug snail arionidae grass gastropod macro wildlife close up crawl closeup mollusk mollusc slimy invertebrate animal ground motion nature slow foot pest ater environment tentacle antenna outdoor pneumostome hermaphrodite arion brush close biology explore forest shiny texture fringe mucus keel mantle striped portrait garden red black slime skirt